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      <title>Spring的异步处理机制 - 交互式测验</title>
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          justify-content: space-between; /* 将按钮分布在两侧 */
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          background-color: #4a90e2;
          color: white;
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          border-radius: 8px;
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          cursor: pointer;
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      </style>
    </head>
    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>Spring的异步处理机制 - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
                <div class="quiz-body">
                    <div class="progress-bar">
                        <div id="progress-indicator"></div>
                    </div>
                    <div id="question-container">
                      <p id="question-text"></p>
                      <ul class="options-list" id="options-list"></ul>
                    </div>
                    <div id="result-container"></div>
                    <div id="hint-container" class="hint-container"></div>
                </div>
                <div class="quiz-footer" id="quiz-footer">
                  <button id="prev-btn" class="nav-btn">上一题</button>
                  <button id="hint-btn" class="nav-btn" style="background-color: #ffc107; color: #333; box-shadow: 0 4px 12px rgba(255,193,7,0.3);">提示</button>
                  <button id="next-btn" class="nav-btn">下一题</button>
                </div>
            </div>
          </div>
      </div>

      <script>
        const quizData = [
  {
    "question": "在Spring应用中，为了启用基于@Async注解的异步方法执行功能，通常需要在配置类上添加哪个注解？",
    "options": [
      "@EnableAsync",
      "@Async",
      "@EnableAspectJAutoProxy",
      "@Configuration"
    ],
    "correctAnswerIndex": 0,
    "explanation": "@EnableAsync是开启Spring异步功能支持的主开关。当这个注解被添加到@Configuration配置类上时，Spring会激活一个后置处理器（AsyncAnnotationBeanPostProcessor），它会扫描所有带有@Async注解的方法，并为它们创建代理，从而实现异步执行。",
    "source": "文档中「1. Spring 异步处理的概述」部分",
    "hint": "文档提到，有一个注解用于'启动 Spring 的异步功能'，并且通常在配置类中使用。"
  },
  {
    "question": "根据文档描述，Spring实现@Async异步功能的底层核心机制是什么？",
    "options": [
      "通过Java的反射机制直接调用方法。",
      "在编译时通过字节码增强技术修改方法。",
      "基于代理模式，为目标方法创建代理对象并交由线程池执行。",
      "依赖于操作系统的多进程调度。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档明确指出，Spring的异步处理是基于代理模式实现的。Spring会为带有@Async注解的Bean创建一个代理对象。当外部调用这个Bean的@Async方法时，实际上是调用了代理对象的方法。代理对象会拦截这个调用，并将其提交给一个TaskExecutor（线程池）来异步执行，然后立即返回，从而不阻塞调用者线程。",
    "source": "文档中「3. 异步任务执行的代理机制」部分",
    "hint": "文档中提到一个关键组件 'AsyncAnnotationBeanPostProcessor' 会为被注解的方法创建什么来实现异步执行？"
  },
  {
    "question": "如果在Spring应用中没有显式配置自定义的TaskExecutor，@Async方法将由哪个默认的执行器来处理？",
    "options": [
      "ThreadPoolTaskExecutor",
      "ForkJoinPool",
      "SimpleAsyncTaskExecutor",
      "ScheduledThreadPoolExecutor"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档中提到，Spring默认使用的TaskExecutor是SimpleAsyncTaskExecutor。这个执行器每次接收到任务时都会创建一个新的线程来执行，并且不会重用线程。因此，在生产环境中，通常建议配置一个更高效的、基于线程池的执行器，如ThreadPoolTaskExecutor，以获得更好的性能和资源管理。",
    "source": "文档中「4. TaskExecutor 的配置和执行」部分",
    "hint": "文档在推荐使用 `ThreadPoolTaskExecutor` 之前，提到了一个Spring默认使用的实现，它不是一个真正的线程池。"
  },
  {
    "question": "当一个@Async注解的异步方法需要返回一个执行结果给调用者时，推荐使用哪种返回类型？",
    "options": [
      "void，并通过一个共享的静态变量来传递结果。",
      "直接返回结果类型，例如 String 或 Object。",
      "Future 或 CompletableFuture。",
      "返回一个 Runnable 对象。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "为了处理异步执行的结果，@Async方法应该返回Future或更强大的CompletableFuture对象。这些对象作为异步计算结果的“占位符”，调用者可以持有这个对象，并在未来的某个时间点通过它来获取实际的计算结果、检查任务是否完成或处理可能发生的异常，而不会在调用时被阻塞。",
    "source": "文档中「5. 异步执行的返回结果处理」部分",
    "hint": "文档中提到了两种可以表示异步执行结果的对象，其中一种是Java 8引入的，提供了更强大的异步编程能力。"
  },
  {
    "question": "要为Spring的异步任务定制一个具有特定核心线程数、最大线程数和队列容量的线程池，最佳实践是什么？",
    "options": [
      "在每个@Async方法内部手动创建和管理一个ThreadPoolExecutor。",
      "修改Spring框架的默认配置文件。",
      "创建一个配置类，实现AsyncConfigurer接口，并重写getAsyncExecutor()方法来提供一个自定义的ThreadPoolTaskExecutor实例。",
      "在application.properties中设置`spring.async.core-pool-size`等属性。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档中的示例代码清晰地展示了自定义异步执行器的标准方式：创建一个带有@Configuration的配置类，实现AsyncConfigurer接口，然后在getAsyncExecutor()方法中构建和配置一个ThreadPoolTaskExecutor实例。这种方式提供了完全的编程控制能力，并且是Spring框架推荐的最佳实践。",
    "source": "文档中「4. TaskExecutor 的配置和执行」部分",
    "hint": "文档中的示例代码展示了一个名为 `AsyncConfig` 的类，它通过实现一个特定的接口来提供一个自定义的 `Executor`。"
  },
  {
    "question": "如果一个标记为@Async的void方法在执行过程中抛出了一个未被捕获的异常，会发生什么情况？",
    "options": [
      "该异常会被Spring框架静默地忽略掉。",
      "调用该异步方法的主线程会立即捕获到这个异常并中断。",
      "异常会被包装在AsyncExecutionException中，但对于void返回类型的方法，默认情况下它只会被日志记录下来。",
      "整个Spring应用会因此而关闭。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "文档第六部分提到，在异步方法执行时，如果出现异常，Spring会将其包装成AsyncExecutionException。对于返回void的方法，这个异常不会传播到调用者线程（因为调用已经返回），所以它通常只会被底层的任务调度器捕获和记录。开发者需要通过try-catch或者配置全局的异步异常处理器来处理这类异常。",
    "source": "文档中「6. 异步方法的异常处理」部分",
    "hint": "文档中提到了Spring会将异步方法中的异常包装成一个特定的异常类型。思考一下，对于一个没有返回值的异步调用，这个异常会如何被感知？"
  },
  {
    "question": "开发者希望在异步任务开始、完成或出错时执行特定的逻辑（如记录日志），可以实现哪个接口来监听这些生命周期事件？",
    "options": [
      "BeanPostProcessor",
      "AsyncListener",
      "TaskLifecycleObserver",
      "ApplicationListener"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档最后一部分明确介绍了`AsyncListener`接口，它提供了`onStart()`, `onComplete()`, `onError(Throwable t)`三个方法。通过实现这个接口，开发者可以精确地挂钩到异步任务执行的各个关键生命周期节点，从而执行自定义的监控、通知或清理操作。",
    "source": "文档中「7. 异步执行的生命周期」部分",
    "hint": "文档的最后一个章节介绍了一个接口，它包含了处理任务开始、完成和出错的回调方法。"
  }
];
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        let currentQuestionIndex = 0;
        let score = 0;
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        const optionsListEl = document.getElementById('options-list');
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        const quizContentEl = document.getElementById('quiz-content');
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        const prevBtn = document.getElementById('prev-btn');
        const nextBtn = document.getElementById('next-btn');
        const hintBtn = document.getElementById('hint-btn');
        const hintContainerEl = document.getElementById('hint-container');

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          optionsListEl.innerHTML = '';
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            return;
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            li.textContent = optionText;
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            // 如果这道题已经回答过，恢复状态
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            userAnswers[currentQuestionIndex] = optionIndex;
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            const isCorrect = optionIndex === currentQuestion.correctAnswerIndex;

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            nextBtn.style.display = 'block';
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            nextBtn.disabled = false; // 最后一题时，下一题按钮不禁用，而是用于显示报告
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                hintContainerEl.style.display = 'none';
                hintContainerEl.textContent = ''; // 清除旧的提示内容
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            if (!isCorrect) {
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            html += `<div class="explanation-text">${questionData.explanation}</div>`;
            html += `<div class="source-text">来源: ${questionData.source}</div>`;
            
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                // 高亮正确答案
                if (index === questionData.correctAnswerIndex) {
                    child.classList.add('correct'); // 需要添加CSS样式
                    child.style.backgroundColor = '#d4edda';
                    child.style.borderColor = '#c3e6cb';
                }
                // 如果选错了，高亮错误选项
                if (!isCorrect && index === userAnswers[currentQuestionIndex]) {
                    child.classList.add('incorrect'); // 需要添加CSS样式
                    child.style.backgroundColor = '#f8d7da';
                    child.style.borderColor = '#f5c6cb';
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                loadQuestion();
            } else {
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            } else {
                hintContainerEl.style.display = 'none';
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        function showFinalScore() {
            document.querySelector('.quiz-body').style.display = 'none';
            document.getElementById('quiz-footer').style.display = 'none';

            const correctCount = score;
            const totalQuestions = quizData.length;
            const answeredCount = userAnswers.filter(a => a !== null).length;
            const wrongCount = answeredCount - correctCount;
            const skippedCount = totalQuestions - answeredCount;
            const accuracy = totalQuestions > 0 ? Math.round((correctCount / totalQuestions) * 100) : 0;
            const errorRate = totalQuestions > 0 ? Math.round((wrongCount / totalQuestions) * 100) : 0;

            const finalScoreHtml =
                '<div class="final-score-container">' +
                '<h2>答题报告</h2>' +
                '<div class="score-summary">' +
                '<div class="score-card">' +
                '<h3>得分</h3>' +
                '<p>' + correctCount + ' / ' + totalQuestions + '</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>正确率</h3>' +
                '<p>' + accuracy + '%</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>错误率</h3>' +
                '<p>' + errorRate + '%</p>' +
                '</div>' +
                '<div class="score-card score-details">' +
                '<table>' +
                '<tr><td>正确</td><td>' + correctCount + '</td></tr>' +
                '<tr><td>错误</td><td>' + wrongCount + '</td></tr>' +
                '<tr><td>未答</td><td>' + skippedCount + '</td></tr>' +
                '</table>' +
                '</div>' +
                '</div>' +
                '<div class="report-actions">' +
                '<button id="review-btn">回顾测验</button>' +
                '<button class="primary" onclick="location.reload()">再试一次</button>' +
                '</div>' +
                '</div>';

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            }
            quizContentEl.insertAdjacentHTML('beforeend', finalScoreHtml);
            document.getElementById('review-btn').addEventListener('click', reviewQuiz);
        }

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                reportEl.remove();
            }

            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
        }

        // Event Delegation for options
        optionsListEl.addEventListener('click', (event) => {
            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  